A raising wheel chair is disclosed which includes a wheel frame, a raising or erecting frame, and a lifting device capable of adjusting the height level of the raising frame, both in the sitting and in the standing position of the user of the raising wheel chair. U.S. Pat. No. 4,076,304 describes a raising wheel chair with a wheel frame and a raising or erecting frame. The erecting frame is provided with a seat, a back rest and foot rests. Both in the sitting position and in the standing position of the user the back rest is kept in upright position by a parallelogram lever. On a transfer from the sitting position to the standing position of the user the foot rests are moved downward and come to rest on the floor. Also the raising wheel chair according to U.S. Pat. No. 4,623,194, which has a somewhat different mechanism functions in the same way.
U.S. Pat. No. 4,054,319 discloses a motorized raising chair on which the feet of the user rest on a platform of the chassis both in the sitting position and in the standing position. This has the advantage that also in the standing position the user can move around with the wheel chair.
WO 01/87219 discloses a wheel chair for use by disabled persons. It has an electrical lifting device which extends from the front region of the wheel frame to the front region of the raising frame and serves for aiding the person to stand up. In order to stand up the user of the chair must glide forward on the seat and remove his feet from the footrest. Operation of the lifting device provides first a slight tilting and then an upward movement of the seat to assist the person to stand up. This assisting device is not suitable for users of wheel chairs, e.g. tetraplegics, who are more than only handicapped in walking.
The disclosures of all of the foregoing patent documents are hereby incorporated by reference in their entireties.
Raising wheel chairs on the market permit the user not only to move from a sitting position to a standing position, but also permit vertical lifting when the user is in the sitting or the standing position. For this purpose a lifting device is provided with which the raising frame can be lifted in the sitting position as well as in the standing position. The lifting or lowering of the sitting or standing level can substantially increase the freedom of action of the user of the wheel chair. It permits the user to reach for objects located in elevated shelves. This obviates costly renovation of his house or apartment. However, these wheel chairs have several disadvantages. They are not permitting driving around in the standing position, because of the danger of overturning. A further disadvantage of certain wheel chairs is that on lifting a backward movement takes place. This may prevent overturning, but makes it difficult or impossible to take objects from an elevated shelve. A further disadvantage of prior art wheel chairs is their limited capability to move over obstacles or to maneuver in narrow space. Finally it may be mentioned that on prior art raising wheel chairs the lifting device can require much space and makes it difficult to obtain access to important parts, (e.g., the batteries) of the raising wheel chair.